Electrical connectors for coupling cables having a bundle of wires are required to be operable under many adverse environmental conditions which include continual vibration, extreme changes in temperature and pressure, minimal space availability, and shock stresses. Various prior constructions of electrical connectors have been proposed utilizing various types of detent means for releasably locking or holding lock means in locked engagement to retain the plug and receptacle means in assembly in full mated electrical and mechanically locked condition.
Some of such prior detent devices have included indicators adapted to be seen, heard and/or felt. U.S. Pat. No. 3,609,632 shows a releasable electrical connector having a lock indicator in the form of a button forced outwardly of an outer shell so that it can be seen and felt. U.S. Pat. No. 3,601,764 shows a locking means for an electrical connector in which visual, audible and feel indicators show when a lock condition is achieved. Such prior constructions were relatively structurally complex and were adapted to the construction of the particular electrical connector.
In some installations, available space is very limited for manipulation of a connector into coupled and uncoupled relation. Often whether or not the coupling is fully electrically mated and mechanically locked cannot be determined visually but can be determined best by an audible and/or tactile indicator. Awareness that a coupling is in full electrical and mechanically locked relation is obviously desirable to assure proper operation of an electrical system. It is also highly desirable to be aware of a fully unlocked unmated condition of the coupling because if partially unlocked coupling parts are separated, damage to the parts caused by applying excessive force or overstressing of the parts may occur.
In an electrical connector in which mating rapidly occurs upon only a part turn of a coupling housing, audible and tactile indicating means must be immediately operable, must be reliable, and should be protected in operation from possible interference by adjacent parts of the connector.